1. Field of Invention
This invention relates to a television device which has a text data processing function and a multiscreen display function and which can receive and display text data in addition to a television signal.
2. Description of Related Art
Recently, wide-screen television devices that have an oblong picture tube for a wide screen and an aspect ratio of 16:9 are widely used. A multiscreen system supports displaying a plurality of images with an aspect ratio of 4:3 on the wide screen by making use of the benefits of the wide screen. The television device of the multiscreen system can display two images. The first image is compressed in the horizontal direction as a parent screen on one side of the wide screen and the second compressed image as a child screen on a space area on the other side of the wide screen. This display mode is known as PIP (Picture In Picture). Further, in a television device of double-screen system (or double-window system), the wide screen can be divided into right and left areas of the same size and images of different broadcasting programs can be simultaneously displayed on the right and left shared screens.
In order to display two images, conventional television devices have two different tuners.
Further, one type of recent broadcasting is a data broadcasting program for transmitting text data multiplexed with the television signal. The text data is multiplexed in the vertical blanking period of the television signal.
One application of the double-screen television device occurs when a normal television broadcasting program and a data broadcasting program are received and an image of the normal television broadcasting program is displayed on one of the shared screens, and an image of the text data of the data broadcasting program is displayed on the other shared screen.
As described above, the double-screen system can be utilized in various configurations of display types. For example a one-screen display mode in which a normal television broadcasting program is received by use of only the first tuner and the image is displayed on the entire area of the wide screen. Another example is a double-screen display mode in which normal television broadcasting programs are received by use of the first and second tuners and respective images are displayed on the left and right screens or a double-screen display mode in which text data is displayed on one of the screens.
However, when the position of the user who utilizes the double-screen system is taken into consideration, a problem may occur particularly when a data broadcast is received. The user does not always fully understand the broadcasting system of text data and the broadcasting system of television program.
Assuming that a normal television broadcast is received by the first tuner of the television receiver of double-screen system, the program is displayed on one of the double screens, a data broadcast is received by the second tuner, and the text data is displayed on the other screen of the double screens. Further, assume that, in this situation, the user watching and listening to the broadcast takes an interest in the text data, sets the one-screen display mode and sets the state in which the data broadcast is received by the first tuner.
In the above case, information pertaining to of the data broadcast supplied to a decoder for the text data cannot be obtained until the operation of the first tuner becomes stabilized. As a result, it is sometimes impossible to see important text data.